Ground station antenna dual bus heterogeneous redundant communication system and method

Abstract

The application relates to the field of satellite TT&C (Tracking, Telemetry and Command) technology, and provides a ground station antenna double-bus heterogeneous redundant communication system and method.The system comprises a main controller, a main switch, a main link transceiver, a fiber conversion module, a main chain copper cable and a plastic optical fiber.The main controller is connected with the main switch and is used for controlling the main switch to switch the main link and the backup link.The main switch is connected with the main link transceiver and the fiber conversion module and is used for switching the main link transceiver and the fiber conversion module.The main link transceiver is connected with the main chain copper cable and is used for sending satellite TT&C instructions.The fiber conversion module is connected with the plastic optical fiber and is used for sending satellite TT&C instructions as the backup link.The scheme can improve the reliability of communication, reduce the maintenance cost and reduce the failure rate.

Description

Technical Field

[0001] This invention relates to the field of satellite telemetry, tracking and command technology, and in particular to a ground station antenna dual-bus heterogeneous redundant communication system and method. Background Technology

[0002] Satellite telemetry and control antennas are a core component of satellite ground stations, undertaking the critical tasks of tracking, telemetry, remote control, and data transmission of satellites in orbit.

[0003] Currently, satellite communication ground station antenna servo control systems generally adopt a dual-copper-cable CAN bus redundancy architecture. This system is used to transmit antenna azimuth / elevation control commands, polarization adjustment parameters, and LNB switching signals in real time within a servo cycle of 4ms, ensuring that the antenna beam is accurately aligned with the satellite. When the main bus error counter counts too high, the main transceiver is shut down, switching to the backup bus and retransmitting the command frame.

[0004] A Chinese patent application (CN202211011257) entitled "A Method, Device, and Medium for Error Recovery of CAN Bus Based on Multiple Device Nodes" discloses the use of dual CAN buses. However, the dual CAN buses use copper cables of the same origin. Under thunderstorm conditions, a single induced lightning surge exceeding 4kV can simultaneously break down the insulation layers of both buses, and electromagnetic pulse coupling can cause common-mode damage to the transceiver chips. Redundancy design becomes meaningless, the system directly fails, requiring manual tower-mounted repairs, and the MTTR (Mean Time To Repair) exceeds 24 hours.

[0005] Chinese patent application number CN2025107047115, entitled "On-orbit Fault Diagnosis and Health Management Method and System Based on Spaceborne Optoelectronic Slip Ring", has no dual redundancy design. Once the main bus is damaged, the entire system will be completely shut down.

[0006] In addition, existing technologies also have the following drawbacks: Switching to the backup bus afterwards requires waiting for the bus error counter to accumulate to a threshold of 96 before triggering the switch, which delays the process by 10-30ms. During the switch, at least 1-3 frames of servo commands are lost (each frame takes approximately 130μs to transmit), causing the antenna servo loop to open. For C-band antennas (beamwidth 0.5°), a pointing error >0.1° may cause them to detach from the satellite's main lobe, resulting in communication interruption.

[0007] The burden of firmware upgrades for slave stations is significant. All slave stations are required to upgrade their firmware to support Error Counter reporting and channel shutdown commands. The azimuth / elevation drivers are located on a 30-meter-high antenna mount, and the LNB controller is at the RF head. On-site upgrades require climbing operations, posing significant safety risks. The round-trip cost for technicians at remote unmanned stations exceeds 5,000 yuan per trip, and the MTTR is greater than 0 during the upgrade process, making "plug and play" impossible.

[0008] Without online monitoring methods, relying solely on a bus error counter, and lacking eye diagram, impedance, and gradual temperature degradation monitoring, slip ring carbon brush wear and cable aging are gradual processes that take months to develop, and the error counter cannot provide early warnings. The system can only passively switch over after communication interruption, failing to achieve predictive maintenance and not meeting the "pre-fault handling" requirements of unattended stations.

[0009] Uncertain software arbitration delays, coupled with MCU software polling of the bus error counter and switching time jitter of ±5ms, mean that servo control requires deterministic delays. Jitter leads to uncertain command arrival times, accumulates calculation errors in the digital PID controller, and causes system oscillations. Especially during high dynamic tracking (angular velocity > 10° / s), delay jitter directly degrades tracking accuracy.

[0010] Therefore, there is a need to provide a ground station antenna dual-bus heterogeneous redundant communication system and method, which can improve communication reliability, reduce maintenance costs, and reduce failure rate.

[0011] The information disclosed in the background section is only intended to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0012] The main purpose of this invention is to overcome the problems of single bus medium, software dependence and lack of monitoring in the existing technology, and to provide a ground station antenna dual-bus heterogeneous redundant communication system and method, which can improve communication reliability, reduce maintenance costs and reduce failure rate.

[0013] To achieve the above objectives, the first aspect of the present invention provides a ground station antenna dual-bus heterogeneous redundant communication system, comprising: a main controller, a main switching switch, a main link transceiver, an optical fiber conversion module, a main link copper cable, and a plastic optical fiber; The main controller is connected to the main switching switch and is used to control the main switching switch to switch between the main link and the backup link; The main switching switch is connected to the main link transceiver and the fiber optic conversion module, and is used to switch between the main link transceiver and the fiber optic conversion module. The main link transceiver is connected to the main link copper cable and is used to send satellite telemetry and control commands; The fiber optic conversion module is connected to a plastic optical fiber and is used as a backup link to send satellite telemetry and control commands.

[0014] According to an exemplary embodiment of the present invention, the ground station antenna dual-bus heterogeneous redundant communication system further includes an analog signal conditioning and monitoring circuit, which is connected to the main controller and is used to monitor the signal eye diagram closure. The main controller controls the main switching switch to switch the main link and the backup link according to the signal eye diagram closure.

[0015] According to an exemplary embodiment of the present invention, the ground station antenna dual-bus heterogeneous redundant communication system further includes a PLC controller. The PLC controller is connected to the main switching switch and serves as a backup controller for the main controller. When the main controller fails, the PLC controller controls the main switching switch to switch between the main link and the backup link.

[0016] According to an exemplary embodiment of the present invention, the PLC controller is connected to the main controller and is also used to monitor the count of the bus error counter and report it to the main controller. The main controller controls the main switching switch to switch the main link and the backup link according to the count of the bus error counter.

[0017] According to an exemplary embodiment of the present invention, the ground station antenna dual-bus heterogeneous redundant communication system further includes a detection operational amplifier and a shunt resistor. The shunt resistor is connected to the main link transceiver and the detection operational amplifier. The detection operational amplifier is connected to the main controller and is used to send a contact impedance analog quantity to the main controller to monitor whether the copper cable equipment of the main link needs to be replaced.

[0018] According to an exemplary embodiment of the present invention, the ground station antenna dual-bus heterogeneous redundant communication system further includes a suppression circuit, which includes a common-mode choke, a TVS protection device, and a high-frequency ferrite bead; the common-mode choke is connected to the TVS protection device, the high-frequency ferrite bead, and the main switching switch.

[0019] As a second aspect of the present invention, the present invention provides a ground station antenna dual-bus heterogeneous redundancy communication method, employing the aforementioned ground station antenna dual-bus heterogeneous redundancy communication system, comprising the following steps: S1: The system powers on and selects the main link transceiver as the main link to send satellite telemetry and control commands; S2: The main controller continuously monitors the link status. If the main link status is abnormal, it instructs the main switch to switch to the fiber optic conversion module and uses the fiber optic conversion module as a backup link to send satellite telemetry and control commands. S3: The main controller continuously monitors the link status. If the main link status returns to normal, it instructs the main switch to switch to the main link transceiver as the main link to send satellite telemetry and control commands. S4: Repeat steps S2 and S3 to ensure uninterrupted operation of the ground station antenna dual-bus heterogeneous redundant communication system.

[0020] According to an exemplary embodiment of the present invention, in step S2, the abnormal status of the main link includes: the bus error counter count reaches a first specified threshold, or the signal eye diagram closure is greater than a second specified threshold and the bit error rate is greater than a third specified threshold.

[0021] According to an exemplary embodiment of the present invention, the second specified threshold is 15%; the third specified threshold is 10%. -7 .

[0022] According to an exemplary embodiment of the present invention, the status of the main controller is continuously monitored throughout the process. If the main controller fails, the PLC controller controls the main switching switch to switch between the main link and the backup link.

[0023] The advantages of this invention are: This solution addresses the issue of simultaneous failure by using two different cable types; it determines the switching timing between the primary and backup links based on the signal eye diagram closure, enabling online monitoring and resolving the technical problem of frame loss during post-switching; and it improves switching efficiency by switching the primary and backup links via a main switch, thereby enhancing communication reliability, reducing maintenance costs, and decreasing the failure rate. Attached Figure Description

[0024] The above and other objects, features, and advantages of this application will become more apparent from the detailed description of exemplary embodiments with reference to the accompanying drawings. The drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0025] Figure 1 The schematic diagram illustrates the structure of a ground station antenna dual-bus heterogeneous redundant communication system.

[0026] Figure 2 The diagram illustrates the steps of a ground station antenna dual-bus heterogeneous redundancy communication method.

[0027] Figure 3 The flowchart of the ground station antenna dual-bus heterogeneous redundancy communication method is illustrated.

[0028] Figure 4 A schematic diagram of the third specific embodiment is shown.

[0029] Figure 5 A schematic diagram of the fourth specific embodiment is shown.

[0030] Figure 6 A schematic diagram of the fifth specific embodiment is shown.

[0031] Figure 7 A schematic diagram of the sixth specific embodiment is shown. Detailed Implementation

[0032] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this application will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0033] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0034] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0035] The flowcharts shown in the accompanying drawings are merely illustrative and do not necessarily include all content and operations / steps, nor do they necessarily have to be performed in the described order. For example, some operations / steps can be broken down, while others can be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0036] It should be understood that although the terms first, second, third, etc., may be used herein to describe various components, these components should not be limited by these terms. These terms are used to distinguish one component from another. Therefore, the first component discussed below may be referred to as the second component without departing from the teachings of this application. As used herein, the term "and / or" includes all combinations of any one and more of the associated listed items.

[0037] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of exemplary embodiments, and the modules or processes in the drawings are not necessarily essential for implementing this application, and therefore cannot be used to limit the scope of protection of this application.

[0038] According to a first specific embodiment of the present invention, the present invention provides a ground station antenna dual-bus heterogeneous redundancy communication system, such as... Figure 1As shown, it includes: main controller U7, main switching switch U30, main link transceiver U1, shunt resistor U12, detection operational amplifier U13, analog signal conditioning and monitoring circuit U11, differential multiplexer U34, first monitoring switch U10, second monitoring switch U32, hardware interlock U33, dual MCU arbitration OR gate U39, fiber optic conversion module, main link copper cable, plastic optical fiber, suppression circuit, multiple joint modules, J1 connector, J2 connector, multiple level conversion chips (including first level conversion chip U31_A, second level conversion chip U31_B, and third level conversion chip U19), redundant OR gate power supply U18, PLC controller U40, temperature sensor U14, LED1, LED2, LED3, R_LED1, R_LED2, and R_LED3.

[0039] The main controller U7 is connected to the main switch U30 and is used to control the main switch U30 to switch between the main link and the backup link. The main controller U7 is also connected to the dual MCU arbitration OR gate U39, the first monitoring switch U10, the second monitoring switch U32, the main link transceiver U1, the analog signal conditioning and monitoring circuit U11, the detection operational amplifier U13, the PLC controller U40, the temperature sensor U14, multiple level conversion chips, R_LED1, and R_LED2.

[0040] The main switching switch U30 is connected to the main link transceiver U1 and the fiber optic conversion module, used to switch between the main link transceiver U1 and the fiber optic conversion module. The main link transceiver U1 is connected to the main link copper cable and used to send satellite telemetry and control commands. The fiber optic conversion module is connected to the plastic optical fiber and used as a backup link to send satellite telemetry and control commands. The analog signal conditioning and monitoring circuit U11 is connected to the main controller U7 and used to monitor the signal eye diagram closure. The main controller U7 controls the main switching switch U30 to switch between the main link and the backup link based on the signal eye diagram closure. The PLC controller U40 is connected to the main switching switch U30 and acts as a backup controller for the main controller U7. When the main controller U7 fails, it controls the main switching switch U30 to switch between the main link and the backup link. The PLC controller U40 is also connected to the main controller U7 and is used to monitor the bus error counter and report it to the main controller U7. The main controller U7 controls the main switching switch U30 to switch between the main link and the backup link based on the bus error counter count. Shunt resistor U12 is connected to the main link transceiver U1 and the detection operational amplifier U13. The detection operational amplifier U13 is connected to the main controller U7 and is used to send an analog value of the contact impedance to the main controller U7 to monitor whether the copper cable equipment of the main link needs to be replaced. The suppression circuit includes a common-mode choke U20, a TVS protection device U21, and a high-frequency ferrite bead U22; the common-mode choke U20 is connected to the TVS protection device U21, the high-frequency ferrite bead U22, and the main switching switch U30.

[0041] Specifically, such as Figure 1As shown, the main controller U7 uses the STM32H743VI chip, including GPIOy port (PD2 pin), first GPIOx port (PC5 pin), second GPIOx port (PB3 pin), first GPIOt port (PF3 pin), FDCAN1-TX port (PA12 pin), FDCAN1-RX port (PA11 pin), ADC2_IN4 (PF4 pin), FDCAN2-TX port (PB6 pin), FDCAN2-RX port (PB5 pin), second GPIOt port (PE3 pin), I2C_SCL port (PB8 pin), I2C_SDA port (PB7 pin), GPIOv port (PE1 pin), GPIOw port (PE0 pin), and VDD port.

[0042] The main switching switch U30 uses HSSW02-CAN15, which includes VDD port, OUT_L port, OUT_H port, BACK_H port, BACK_L port, MAIN_H port, MAIN_L port, IN port, and FLT port.

[0043] The main link transceiver U1 uses the MCP2562FD, which includes RXD port, TXD port, CANL port, CANH port, and STYB port.

[0044] The shunt resistor U12 is an LR2512-R010-F, including FORCE+, FORCE-, SENSE+, and SENSE- ports. The detection operational amplifier U13 is an ADA4522-1, including IN+, IN-, and OUT ports.

[0045] The analog signal conditioning and monitoring circuit U11 uses the ADA4522-1, including IN+, IN-, OUT, V+, and V- ports. The differential multiplexer U34 uses the MAX14757, including OUT_H, OUT_L, IN1_H, IN1_L, SEL, IN2_H, and IN2_L ports. The first monitoring switch U10 includes MAIN_H, MAIN_L, IN, OUT_H, and OUT_L ports. The second monitoring switch U32 includes IN, BACK_H, BACK_L, OUT_H, and OUT_L ports.

[0046] The hardware interlock U33 uses a 74LVC2G74DC, including CLK, CLR, GND, VCC, D, PRE, and Q ports. The dual MCU arbitration OR gate U39 uses a 74LVC1G32, including 1A, 1Y, GND, 1B, and VCC ports.

[0047] The fiber optic conversion modules include a CAN-to-fiber optic module U15 and a fiber optic-to-CAN module U41. The CAN-to-fiber optic module U15 uses an ESD-OMC210 and includes CANA_H, CANA_L, SD, RXD, TXD, POF_TX, and POF_RX ports. The fiber optic-to-CAN module U41 also uses an ESD-OMC210 and includes POF_TX, POF_RX, CANA_H, and CANA_L ports. The plastic optical fibers include fiber optic 1 and fiber optic 2.

[0048] The suppression circuit includes a common-mode choke U20, a TVS protection device U21, and a high-frequency ferrite bead U22. The common-mode choke U20 is an ACT45B-510-2P, including IN_H, IN_L, OUT_H, and OUT_L ports. The TVS protection device U21 is an SMCJ12CA, including A and K ports. The high-frequency ferrite bead U22 is a 0.1Ω / 100MHz ferrite bead, including PAD_IN_H, PAD_IN_L, PAD_OUT_L, and PAD_OUT_H ports.

[0049] Multiple joint modules include a first joint module U36, a second joint module U37, and a third joint module U38. The first joint module U36 includes CANA_H, CANA_L, CANB_H, and CANB_L ports. The second joint module U37 includes CANA_H, CANA_L, CANB_H, and CANB_L ports. The third joint module U38 includes CANA_H and CANA_L ports.

[0050] Multiple level conversion chips are included, comprising a first level conversion chip U31_A, a second level conversion chip U31_B, and a third level conversion chip U19. The first level conversion chip U31_A uses a 74LVC1T45 chip and includes ports A1, B1, VCCA, and VCCB. The second level conversion chip U31_B uses a 74LVC1T45 chip and includes ports A1, B1, VCCA, and VCCB. The third level conversion chip U19 uses a TPS62160 and includes ports VIN and VOUT. A redundant OR gate power supply U18 uses an LT4412 and includes ports VIN and VOUT.

[0051] The U40 PLC controller uses GCAN-530C, which includes ERROR port, GPIO_OUT port, CAN_L port, and CAN_H port.

[0052] The temperature sensor U14 uses a TMP117AIDR, which includes an SDA port, an SCL port, a GND port, and a VDD port. LED1, LED2, LED3, R_LED1, R_LED2, and R_LED3 each have a first port and a second port. The resistance of R_LED1, R_LED2, and R_LED3 is 330Ω.

[0053] like Figure 1 As shown, in the connection relationships of the various devices, the signal flow direction follows the direction of the arrows. Figure 1 The lines arranged in a cross shape are not connected.

[0054] The GPIOy port (PD2 pin) of the main controller U7 is connected to the FLT port of the main switch U30 to read hardware fault status, such as over-temperature and over-current. The main switch U30 reports over-temperature / over-current faults in real time. This connection triggers an interrupt in the main controller U7 and forces hardware interlocking, locking the system to a safe state. This is a key fault diagnosis link for achieving MTTR=0. After reading the hardware fault status inside the main switch U30 (HSSW02-CAN15 high-speed redundant switch), the main controller U7 executes the hardware interlocking safety strategy: 1. Immediately lock the main switch U30 to prevent illegal switching; 2. Trigger system safety protection, forcibly cutting off the power supply to the relevant links or entering an emergency stop state; 3. Ensure MTTR=0 (zero fault repair time) while preventing the fault from escalating to bus paralysis. The first GPIOx port (PC5 pin) is connected to port 1A of the dual MCU arbitration OR gate U39 to issue link switching commands. The second GPIOx port (PB3 pin) is connected to the CLK port of hardware interlock U33, the IN port of the second monitoring switch U32, and the IN port of the first monitoring switch U10, for synchronous switching of the monitoring channel and the main / backup link. The first GPIOt port (PF3 pin) is connected to the OUT port of the analog signal conditioning and monitoring circuit U11, for acquiring the eye diagram closure data of the bus signal after processing by the analog signal conditioning and monitoring circuit U11, for signal quality monitoring, and for judging the link quality. The bus signal flows to the input of the analog signal conditioning and monitoring circuit U11 (analog signal conditioning circuit), and after being amplified / filtered / extracted by the analog signal conditioning and monitoring circuit U11, it is output from the OUT port of the analog signal conditioning and monitoring circuit U11 and sent to the PF3 port of the main controller U7 for analog-to-digital conversion (ADC) acquisition. The FDCAN1-TX port (PA12 pin) is connected to the TXD port of the main link transceiver U1, for sending CAN-FD data to the main link transceiver U1. The FDCAN1-RX port (PA11 pin) connects to the RXD port of the master transceiver U1 and is used to receive CAN-FD data transmitted from the bus. The FDCAN1-TX and FDCAN1-RX ports enable bidirectional TTL level transmission of master-link CAN-FD data: Master controller U7's FDCAN1-TX port → Master transceiver U1's TXD port: Master controller U7 sends CAN-FD data frames (1 Mbps baud rate, 8 bytes data segment) at 3.3V TTL logic level via FDCAN1_TX. The master transceiver U1 receives these frames and converts them into a 5V differential signal to drive the bus. Master transceiver U1's RXD port → Master controller U7's FDCAN1-RX port: The master transceiver U1 receives the 5V differential acknowledge signal returned from the slave driver, converts it to 3.3V TTL level, and transmits it to the master controller U7 via FDCAN1_RX, completing closed-loop communication. ADC2_IN4 (PF4 pin) is connected to the OUT port of the detection operational amplifier U13 to collect bus contact impedance for slip ring wear warning. FDCAN2-TX (PB6 pin) is connected to the A1 port of the first level conversion chip U31_A to send data to the fiber optic conversion module (backup link). FDCAN2-RX (PB5 pin) is connected to the A1 port of the second level conversion chip U31_B to receive data returned from the fiber optic conversion module. The second GPIOt (PE3 pin) is connected to the ERROR port of the PLC controller U40 to read the bus error counter count reported by the PLC controller U40. I2C_SCL (PB8 pin) is connected to the SCL port of the temperature sensor U14 to obtain the clock data of the temperature sensor U14. I2C_SDA (PB7 pin) is connected to the SDA port of the temperature sensor U14 to obtain the temperature data of the temperature sensor U14. The GPIOv port (PE1 pin) is connected to the second port of R_LED2 to control the green light. A low level indicates that the main link (copper cable CAN-FD) communication is normal and the system is in normal operation. The GPIOw port (PE0 pin) is connected to the second port of R_LED1 to control the red light. A low level indicates a main link failure, and the system has switched to the backup link (fiber optic POF) in redundant backup operation. The VDD port is connected to the OUT port of the third level conversion chip U19 to power the 3.3VI / O port. Please refer to Table 1 for the pin connections of the main controller U7.

[0055] Table 1

[0056] The VDD port of the main switch U30 is connected to a 5V power supply. The OUT_L port is connected to the IN_L port of the common-mode choke U20, serving as the differential low-level terminal for the external bus, used to drive the motor joint module; CAN_L is the differential negative. The OUT_H port is connected to the IN_H port of the common-mode choke U20, serving as the differential high-level terminal for the external bus, used to drive the motor joint module; CAN_H is the differential positive. The OUT_H and OUT_L ports of the main switching switch U30 simultaneously perform both external driving and disturbance-free monitoring functions. Their connection to the analog signal conditioning and monitoring circuit U11 is as follows: OUT_H (differential positive / CAN_H): One path drives the joint module through the H pin of connector J1; the other path connects to the IN+ pin of analog signal conditioning and monitoring circuit U11 via a 100kΩ high-impedance tap, acquiring eye diagram signals and sending them to U7 for bit error rate prediction. OUT_L (differential negative / CAN_L): One path drives the joint module through the L pin of connector J1; the other path connects to the IN- pin of analog signal conditioning and monitoring circuit U11 via a 100kΩ high-impedance tap, working in conjunction with the IN+ pin to achieve differential eye diagram monitoring, sending the signals to the main controller U7 for predictive maintenance. While driving the joint module, the OUT_H and OUT_L ports, through the disturbance-free tap of the high-impedance network, are connected to the differential input pins of analog signal conditioning and monitoring circuit U11 respectively, realizing online monitoring of the bus eye diagram and predictive maintenance. The BACK_H port connects to the CANA_H port of the CAN-to-fiber optic module U15, and is used to output the backup link fiber differential positive signal to the bus. The BACK_L port connects to the CANA_L port of the CAN-to-fiber optic module U15, and outputs the backup link fiber differential negative signal to the bus. The BACK_H and BACK_L ports enable heterogeneous redundancy switching. When the main link (copper cable) fails due to lightning surges, impedance drift, or other faults, the main switching switch U300 switches the communication path from MAIN to BACK within <150ns. The photoelectric conversion signal of the CAN-to-fiber optic module U15 is input through BACK-H / L to ensure uninterrupted communication of the antenna servo system. The MAIN_H port is connected to the CANH port of the main link transceiver U1, and is used to output the main link differential positive signal to the bus. When the main switch U30 selects the main link, it transmits the 5V differential positive signal converted by the main link transceiver U1 bidirectionally (receiving both the drive signal sent by the main link transceiver U1 to the bus and the acknowledgment signal returned by the slave station). Together with the MAIN_L port, it forms a 120Ω differential pair, realizing the physical layer bidirectional data path for the main link CAN-FD communication. The MAIN_L port is connected to the CANH port of the main link transceiver U1, and outputs the main link differential negative signal to the bus. When the main switch U30 selects the main link, it transmits the 5V differential negative signal converted by the main link transceiver U1 bidirectionally.The CANH port of the main link transceiver U1 is connected to the MAIN_H port of the main switch U30. This connection is primarily used to bidirectionally transmit the 5V differential positive signal converted by the main link transceiver U1 when the main switch U30 selects the main link (receiving both the drive signal sent by the main link transceiver U1 to the bus and the acknowledgment signal returned by the slave station). Together with MAIN_L, they form a 120Ω differential pair, realizing a bidirectional physical layer data path for the main link CAN-FD communication. This is the main channel input port for primary / backup redundancy switching. The CANL port of the main link transceiver U1 is connected to the MAIN_L port of the main switch U30. This connection is primarily used to bidirectionally transmit the 5V differential negative signal converted by U1 when U30 selects the main link (receiving both the drive signal sent by the main link transceiver U1 to the bus and the acknowledgment signal returned by the slave station). Together with MAIN_H, they form a 120Ω differential pair, realizing a bidirectional physical layer data path for the main link CAN-FD communication. This is the main channel input port for primary / backup redundancy switching. The IN port connects to the 1Y port of the dual MCU arbitration OR gate U39 to receive the master / backup channel switching command actively issued by the master controller U7. A high level indicates the master link, and a low level indicates the backup link, achieving hardware switching within <150ns. This is the core execution path that determines the system's MTTR=0. The FLT port also connects to the CLR port of the hardware interlock U33, providing over-temperature / over-current open-drain output to indicate hardware faults. The master switch U30 is the physical carrier for achieving the five major innovations of this solution: heterogeneous redundancy, hardware arbitration, zero frame loss, predictive maintenance, and plug-and-play. If the master link transceiver U1 is directly connected to the bus, the system degenerates into a traditional software redundancy architecture, rendering all technical effects ineffective and resulting in a loss of innovation. The master switch U30 is a 10-pin TSSOP with a <150ns timeframe; please refer to Table 2 for pin connection relationships.

[0057] Table 2

[0058] The main link transceiver U1 is connected to the main link copper cable and is used to send satellite telemetry / control / antenna servo commands to the motor joint module via the copper cable bus. The CANL port of the main link transceiver U1 is the negative terminal for the CAN bus driver, connected to the FORCE+ port of the shunt resistor U12, the MAIN_L port of the first monitoring switch U10, and the MAIN_L port of the main switching switch U30, for outputting a differential negative to the main switching switch U30. The CANH port is the positive terminal for the CAN bus driver, connected to the FORCE- port of the shunt resistor U12, the MAIN_H port of the first monitoring switch U10, and the MAIN_H port of the main switching switch U30, for outputting a differential positive to the main switching switch U30. The STYB port is grounded, forcing the chip into normal operating mode (without sleep mode); this is because the antenna pointing control period is 4ms, requiring a communication delay of <1ms. If STBY is left floating or controlled, a wake-up delay >5μs after mistakenly entering Standby mode may result in 1-2 frame losses and a pointing error >0.1°. Hard grounding (0Ω resistor) prevents CPU software misconfiguration of GPIO, which could cause STBY to go high, and is a concrete manifestation of "hardware safety redundancy." Even if the main controller U7 crashes or the watchdog resets, the main link transceiver U1 remains in Normal mode, ensuring uninterrupted bus communication, conforming to the "fail-safe" principle of unattended stations. See Table 3 for the pin connections of the main link transceiver U1.

[0059] Table 3

[0060] The SENSE+ port of shunt resistor U12 is connected to the IN+ port of detection operational amplifier U13 to detect the positive terminal of the voltage across shunt resistor U12; the SENSE- port is connected to the IN- port of detection operational amplifier U13 to detect the negative terminal of the voltage across shunt resistor U12. Detection operational amplifier U13 amplifies this voltage difference and sends it to the main controller. The bus contact impedance is calculated using voltage and current conversion, enabling online monitoring and early warning of slip ring wear, cable aging, and poor contact. The pin connections of shunt resistor U12 and detection operational amplifier U13 are shown in Table 4.

[0061] Table 4

[0062] The IN+ port of the analog signal conditioning and monitoring circuit U11 is connected to the OUT_H port of the differential multiplexer U34 to select the differential positive signal. After selecting one of the two links (main / backup), the differential multiplexer U34 outputs the CAN differential positive signal (CAN_H) of that link to the IN+ port of the analog signal conditioning and monitoring circuit U11 for eye diagram monitoring. The IN- port is connected to the OUT_L port of the differential multiplexer U34 to select the differential negative signal. The V+ port is connected to a 3.3V power supply, and the V- port is connected to a 0V power supply. The pin connections of the analog signal conditioning and monitoring circuit U11 are shown in Table 5.

[0063] Table 5

[0064] The IN1_H port of the differential multiplexer U34 is connected to the OUT_H port of the first monitoring switch U10 for primary monitoring of the differential positive signal, corresponding to the CAN_H port of the main link (copper CAN bus) (the positive signal line of the differential signal of the main link copper CAN bus); the IN1_L port is connected to the OUT_L port of the first monitoring switch U10 for primary monitoring of the differential negative signal. The SEL port is connected to the Q port of the hardware interlock U33 for channel selection control. The IN2_H port is connected to the OUT_H port of the second monitoring switch U32 for backup monitoring of the differential positive signal; the IN2_L port is connected to the OUT_L port of the second monitoring switch U32 for backup monitoring of the differential negative signal. The pin connections of the differential multiplexer U34 are shown in Table 6.

[0065] Table 6

[0066] The BACK_H port of the second monitoring switch U32 is connected to the CANA_H port of the CAN-to-fiber optic module U15 for backup link differential positive input and backup link (plastic fiber optic CAN) CAN_H differential positive signal, which is then connected to the monitoring switch for online signal quality monitoring. The BACK_L port is connected to the CANA_L port of the CAN-to-fiber optic module U15 for backup link differential negative input. The pin connections of the two monitoring switches are shown in Table 7.

[0067] Table 7

[0068] The GND port of hardware interlock U33 is connected to 0V, and the VCC port is connected to the VOUT port of the third level conversion chip U19, which is 3.3V. The D port and PRE port are connected to 3.3V power supply. The pin connection relationship of hardware interlock U33 is shown in Table 8.

[0069] Table 8

[0070] The GND port of the dual MCU arbitration OR gate U39 is connected to 0V, and its 1B port is connected to the GPIO_OUT port of the PLC controller U40 to receive the passive takeover signal from the PLC controller U40; the VCC port is connected to a 3.3V power supply. The pin connections of the dual MCU arbitration OR gate U39 are shown in Table 9.

[0071] Table 9

[0072] The OUT_H port of the common-mode choke U20 is connected to the A port of the TVS protection device U21 and the PAD_IN_H port of the high-frequency ferrite bead U22. This is used to output the filtered differential positive bus signal and to perform surge protection and high-frequency noise suppression. The OUT_L port is connected to the K port of the TVS protection device U21 and the PAD_IN_L port of the high-frequency ferrite bead U22. This is used to output the filtered differential negative bus signal and to perform surge protection and high-frequency noise suppression. The pin connections of the common-mode choke U20 are shown in Table 10.

[0073] Table 10

[0074] TVS protection device U21 is used for surge protection. The pin connection of TVS protection device U21 is shown in Table 11.

[0075] Table 11

[0076] The PAD_OUT_L port of the high-frequency ferrite bead U22 is connected to the CAN_L port of the PLC controller U40, and then to the CANA_L port of the first joint module U36 via a J1 connector; the PAD_OUT_H port is connected to the CAN_H port of the PLC controller U40, and then to the CANA_H port of the first joint module U36 via a J1 connector. The high-frequency ferrite bead U22 is used to filter noise and output a purified signal. The noise is high-frequency electromagnetic interference noise on the CAN bus, and the purified signal is a clean CAN differential communication signal, supplied to the PLC controller U40 and the joint module U36. The pin connections of the high-frequency ferrite bead U22 are shown in Table 12.

[0077] Table 12

[0078] The SD port of the CAN-to-fiber optic module U15 is connected to the first port of R_LED3 for optical power normal indication; a low level indicates normal operation. The RXD port is connected to the B1 port of the second level conversion chip U31_B for outputting 5V receive data to the level converter, achieving level matching between the 5V fiber optic module domain and the 3.3V MCU domain. The TXD port is connected to the B1 port of the first level conversion chip U31_A for receiving the level-converted 5V transmit data, achieving safe level matching between the 3.3V MCU domain and the 5V fiber optic module domain to prevent chip damage. The two chips are used to completely separate the transmit and receive channels, avoiding signal interference and ensuring stable and reliable communication. The POF_TX port is connected to the POF_RX port of the fiber optic-to-CAN module U41 via connector J2 and fiber optic cable 1 for 650nm optical signal output. The POF_RX port is connected to the POF_TX port of the fiber optic-to-CAN module U41 via connector J2 and fiber optic cable 2 for 650nm optical signal input. The pin connections of the CAN-to-fiber optic module U15 are shown in Table 13.

[0079] Table 13

[0080] The CANA_H port of the fiber optic to CAN module U41 is connected to the CANA_H port of the first joint module U36, and the CANA_L port is connected to the CANA_L port of the first joint module U36. The pin connections of the fiber optic to CAN module U41 are shown in Table 14.

[0081] Table 14

[0082] Ground station antennas can be biaxial or triaxial. Multiple articulated modules are a common configuration for ground station antennas. One module is used for 0-90 degree elevation movement, another for 0-360 degree azimuth rotation, and the third, once the azimuth and elevation are determined, rotates the feed or sub-reflector 0-270 degrees to align the antenna's electric field vector with the satellite's downlink polarization direction, reducing polarization loss. The CANB_H port of the first articulated module U36 connects to the CANA_H port of the second articulated module U37, and the CANB_L port connects to the CANA_L port of the second articulated module U37. The CANB_H port of the second articulated module U37 connects to the CANA_H port of the third articulated module U38, and the CANB_L port connects to the CANA_L port of the third articulated module U38.

[0083] The first level conversion chip U31_A is the level conversion chip for the transmitting channel. Its VCCB port is connected to a 5V power supply, and its VCCA port is connected to the VOUT port of the third level conversion chip U19. The first level conversion chip U31_A adopts a unidirectional fixed transmission mode. After the OE pin is grounded, the chip is always in the output enabled state and does not require software control. In the system, it is a static configuration with fixed grounding and no dynamic control logic. Therefore, only the core signal pins are marked in the schematic diagram, and the statically grounded enable pin is omitted. The pin connection relationship of the first level conversion chip U31_A is shown in Table 15.

[0084] Table 15

[0085] The second level conversion chip U31_B is the level conversion chip for the receiving channel. Its VCCB port is connected to a 5V power supply, and its VCCA port is connected to the VOUT port of the third level conversion chip U19. The output enable pin of the second level conversion chip U31_B for the receiving channel is active low. In this scheme, it is directly grounded to fix the unidirectional transmission from B to A. Because it is a static configuration, it is simplified and omitted in the schematic diagram. The pin connection relationship of the second level conversion chip U31_B is shown in Table 16.

[0086] Table 16

[0087] The first level conversion chip U31_A and the second level conversion chip U31_B replace the dedicated VIO transceiver (cost > 0.5 USD), reducing the BOM cost by 0.32 USD / node and improving supply chain flexibility. Here, BOM is an abbreviation for Bill of Materials.

[0088] This scheme adopts a heterogeneous medium collaborative mechanism of main chain copper cable and plastic optical fiber, and has the characteristics shown in Table 17.

[0089] Table 17

[0090] The VOUT port of the third level conversion chip U19 is also connected to the first port of LED1, the first port of LED2, the second port of LED3, and the VDD port of the temperature sensor U14 to provide a 3.3V power supply. The VIN port of the third level conversion chip U19 is connected to the VOUT port of the redundant OR gate power supply U18 to obtain a 12V power supply. The VIN port of the redundant OR gate power supply U18 is connected to a 6.5V to 17V power supply.

[0091] The GND port of temperature sensor U14 is connected to 0V. The second port of LED1 is connected to the first port of R_LED1; the second port of LED2 is connected to the first port of R_LED2; the first port of LED3 is connected to the second port of R_LED3. LED3 is a third-color LED and an alarm light. Figure 1 Yellow indicates a warning / fault, signifying eye diagram degradation, impedance exceeding limits, or system alarm / fault risks, prompting maintenance personnel to investigate.

[0092] PLC controller U40 is a backup device for the main controller U7. Normally, it doesn't operate, only silently monitoring the bus. If the main controller U7 "malfunctions" (becomes inoperable) or the bus becomes critically ill (almost unusable), PLC controller U40 immediately takes over, issuing commands to ensure the system doesn't crash. However, it doesn't intervene in the main controller U7's instruction scheduling and data forwarding processes. When the main controller U7 becomes inoperable (heartbeat timeout > 100ms) or the bus health deteriorates to the Error Counter threshold > 96, PLC controller U40 automatically switches from monitoring mode to decision mode. It triggers the main switch U30 via the GPIO_OUT pin to perform a master-slave switchover, completing the heterogeneous media switching. This is primarily to avoid the risk of single-point decision failure. The GND port of PLC controller U40 should be connected to 0V reference ground. This solution employs a single-point grounding strategy, connecting the J1 connector to the system GND at a single point to avoid loop interference. Since this pin is a global static ground signal, it is already uniformly represented in the schematic diagram through external system connections and is not separately labeled, conforming to circuit drawing specifications. The pin connections of the PLC controller U40 are shown in Table 8.

[0093] Table 18

[0094] In practice: This solution is designed for industrial applications, with the following environmental parameters: altitude 4500m (plateau station), salt spray C5-M (coastal station), temperature difference 60℃, EMI ±1kV lightning surge. Device requirements: wide temperature range -40~85℃, 3kV surge protection, 30% salt spray.

[0095] 1. The hardware configuration parameters of the above heterogeneous redundant links are shown in Table 19: Table 19

[0096] 2. Progressive Degradation Sampling Circuit: This circuit provides the hardware foundation for predictive maintenance. The progressive degradation sampling circuit is an analog front-end circuit that performs non-destructive, high-resolution, real-time acquisition of CAN bus physical layer parameters (eye diagram amplitude, edge slope, contact impedance, temperature). It monitors performance degradation that changes slowly over a timescale of several months (slip ring brush wear, cable oxidation, connector aging). The sampling bandwidth is designed to be 1kHz-10kHz (far lower than the CAN signal bandwidth). By accumulating 400 sampling points (10ms window), it generates an average value, suppresses random noise, and extracts the progressive degradation trend.

[0097] Eye height sampling: The MCU's built-in ADC3 (STM32H743VI) continuously acquires the OUT_H / L differential signal of the main switching switch U30 at a rate of 3.6MSPS. The TIM2 timer is triggered once every 25ns. After accumulating 400 times, an average eye height value of 10ms is generated with a resolution of 12bit and a temperature drift of less than 0.5LSB / ℃.

[0098] Contact resistance detection: A 10mΩ precision shunt resistor U12 (LR2512-R010-F) is connected in series on the main chain CAN-H line. The detection operational amplifier U13 achieves 100x differential amplification, and ADC2 performs sampling with a resolution of 0.5mΩ, which can detect degradation at the 5mΩ level.

[0099] Temperature monitoring: The TMP117AIDR digital temperature sensor U14 with I²C interface and an accuracy of ±0.1℃ is used. It is deployed in the copper foil area below the main switching switch U30 to monitor the board-level hot spot temperature in real time.

[0100] LSTM algorithm (deployed on-chip in main controller U7): Based on DSP instruction acceleration of STM32H743, it processes eye diagram, impedance, and temperature three-channel timing data with a 10ms sliding window to predict the bit error rate (BER) for the next 200ms. When BER ≥ 10... -7 At this time, the hardware directly triggers the IN / switching control port of the main switching switch U30 to flip, avoiding the inevitable frame loss during subsequent switching.

[0101] 3. EMC and Salt Spray Protection: The main chain and backup chain CAN differential signals are suppressed in three stages: Common mode choke U20: ACT45B-510-2P (100MHz, impedance 1000Ω); TVS protection period U21: SMCJ12CA bidirectional TVS (12V, 600W, response time <1ps); High-frequency ferrite bead U22 filter: 0.1Ω / 100MHz ferrite bead to transceiver; External connector: JST ZHR-4 gold-plated terminals (30µin thickness), PPS GF40 plastic housing, CTI≥600, contact resistance increase <2mΩ after 18 months of salt spray testing.

[0102] POF interface: HFBR-4501Z metal clip, IP67 protection, 316L stainless steel material, no corrosion after 1000 hours of salt spray; POF cable outer diameter 2.2mm, inner lining PTFE (PTFE is an abbreviation for Polytetrafluoroethylene, commonly known as Teflon), minimum bending radius 20mm, optical attenuation <0.2dB after 5 million drag chain cycles.

[0103] 4. Hardware interlocks and diagnostics: The FAULT pin (open drain) of the TSX63111 (i.e., the FLT port of the main switch U30) is connected to the CLR terminal of the hardware interlock U33. Any solid-state switch (main switch) will pull the CLR low due to overheating or overcurrent, forcing the interlock to reset. The MCU reads the FAULT status through GPIO and immediately reports a "hardware fault" alarm to prevent software faults from causing double-on or double-off states.

[0104] Onboard LED status indicators: Red LED1: Main chain error, switched to fiber optic; Green LED2: Main chain is operating normally; Yellow LED3: POF backup link failure (no light signal or SD=1); Debugging interface: UART1 (3.3V, 115200-8-N-1) is retained, outputting real-time eye height, impedance, temperature and P_risk data, which is convenient for tower crane maintenance personnel to use the USB-TTL module for on-site troubleshooting without disassembling the antenna mount.

[0105] 5. Redundant power supply: The gateway power input adopts a dual 12V redundant design. The main power supply comes from the ground station UPS, and the backup power supply comes from solar power and batteries. The "OR" logic power supply is implemented through the LT4412IS6 ideal diode, with a switching time of <0.5µs, ensuring continuous power supply without interruption. The on-board DC-DC converter uses TPS62160DSGR (output 3.3V / 1A), with an efficiency of 95%, supports 6.5~17V input transients, and meets the ±100V / 1ms surge requirements.

[0106] The innovative aspects of this solution are: 1. Heterogeneous media predictive redundancy architecture: Existing technical defects: CN111614532A and CN216122468U both use dual copper cable redundancy, which cannot resist common faults such as EMP and induced lightning strikes; CN115484124A uses dual CAN, but relies on Error Counter (bus error counter) to switch afterward, and frame loss is unavoidable.

[0107] This solution employs a novel heterogeneous media approach: a main link copper cable + a backup link plastic optical fiber (POF). The main controller U7's on-chip ADC monitors eye diagram closure in real time. When BER ≥ 10... -7 Hardware-triggered switching is initiated 200ms in advance.

[0108] Unexpected results: Avoiding same-source failures, achieving 0 frame loss, and MTTR < 4ms (less than the servo cycle).

[0109] 2. Single-chip hardware decision-making and switching: Existing technical defects: CN111614532A requires DSP+FPGA+dual transceiver software arbitration, with a switching delay >10ms; CN216122468U, although using dual controllers, still requires software judgment and lacks hardware arbitration.

[0110] This solution uses only a single 10-pin high-speed solid-state switch HSSW02-CAN15 (main switching switch U30) to complete the MAIN / BACK differential pair switching, with built-in comparator hardware judgment, eliminating the need for a separate arbitration MCU.

[0111] Unexpected results: switching latency <150ns, jitter <5ns, and BOM cost reduced by $2.3 per node.

[0112] 3. Transparent redundancy and self-healing mechanism on the main station side: Existing technical defects: CN111614532A requires the slave station to parse the SN number and participate in the redundancy logic, so the firmware must be upgraded; CN115484124A requires the problematic node to be reset and cannot be plug-and-play.

[0113] This solution employs the following approach: redundant logic is fully integrated on the main station gateway side, requiring zero modification to the slave stations (azimuth / tilt joint modules, LNB controllers); and automatically switches back to the main link within 1 second after a fault is recovered.

[0114] Unexpected results: Achieve MTTR=0 (business is unaware), on-site maintenance without downtime, and maintenance-free for remote sites.

[0115] 4. On-chip physical layer online monitoring: Existing technical defects: CN120357952A monitors the secondary power supply voltage (+5V / -5V) and cannot detect CAN signal degradation; CN120630837A uses an on-chip ADC but only monitors relay current (not the CAN physical layer).

[0116] This solution reuses the on-chip ADC1_IN3 channel of the main controller U7 to sample the amplitude / edge of the OUT_H / L signal with high impedance, without adding an external monitoring MCU.

[0117] Unexpected results: Eliminates the need for an external ADC (0.5 USD), predictive maintenance response time is less than 200ms, and provides early warning of slip ring and carbon brush wear.

[0118] 5. Universal level converter to replace VIO transceiver: Existing technical defects: CN111614532A and CN216122468U use dedicated CAN transceivers and do not optimize level matching costs; CN120630837A uses 74LVC1T45 but does not quantify cost advantages.

[0119] This solution uses a 74LVC1T45 general-purpose level conversion chip to replace the dedicated transceiver with VIO pins, providing bidirectional matching for 5V and 3.3V.

[0120] Unexpected results: BOM cost reduced by USD 0.32 / node, supply chain flexibility improved, and the risk of relying on a single supplier was mitigated.

[0121] As a second specific embodiment of the present invention, the present invention provides a ground station antenna dual-bus heterogeneous redundancy communication method, which adopts the ground station antenna dual-bus heterogeneous redundancy communication system described in the first specific embodiment, such as... Figure 2 and Figure 3 As shown, it includes the following steps: S1: The system powers on and selects the main link transceiver as the main link to send satellite telemetry and control commands.

[0122] Upon power-on initialization, the GPIOx port of the main controller U7 is set to 1, the default main link (copper cable) is enabled, and the hardware monitoring loop is entered.

[0123] The main controller U7 sends a CAN frame via its FDCAN-TX port. The main switch U30 selects the main link copper cable, and the data is converted into a differential signal by the main link transceiver U1 and broadcast to all slave stations via the main link copper cable, thus solving the "slave station firmware upgrade" problem. The CAN frame is a satellite telemetry and control command frame, a communication data unit carrying satellite telemetry and control commands and antenna servo control data. It carries the core application layer data of the antenna servo control system and serves as the sole data source. The main controller U7 sends it once via FDCAN-TX, and the main switch U30 automatically distributes it to the main / backup link. Slave stations do not need to identify redundant logic, achieving plug-and-play functionality with zero firmware upgrade. The functions of the CAN frame are: 1. Transmitting telemetry and control commands and core control data; 2. Sending it uniformly by the main controller U7 and automatically distributing it to the main and backup links via the main switch U30; 3. Allowing slave stations to upgrade without identifying redundant logic, achieving plug-and-play functionality with zero firmware upgrade.

[0124] The slave station's response data is returned along the main link copper cable, and the main switch U30 synchronously switches the receiving channel to the main link. The slave station returns a joint module status feedback frame, which specifically includes: Current angle: Real-time position of the encoder, used for closed-loop PID calculation; Current speed: Motor speed feedback; Fault codes: overcurrent, overtemperature, encoder failure, etc. Checksum: CRC8 checksum, ensuring the integrity of the returned data; Response timing: The slave station must respond within 2ms after receiving the command frame to form a servo closed-loop control.

[0125] The antenna servo control command data is sent only once from a single TX pin of the MCU, without distinguishing between the primary and backup links; this data is a satellite telemetry and control command frame, which is transmitted only once like a radio broadcast, but the "smart distributor" of the primary switch U30 will send it to both the copper cable and the optical fiber simultaneously, so the slave station hears the same content regardless of which path it receives from. Redundancy decisions are made entirely on the gateway side: the primary switch U30 chip automatically completes the primary / backup selection without the need for the joint module to participate in the redundancy logic. Zero-awareness from the slave station: The data received by the slave station (joint module) is completely consistent with that of the ordinary CAN bus, requiring no firmware modification; Direct solution: The slave station does not need to upgrade its firmware, achieving plug-and-play functionality and eliminating the "ecosystem lock-in" dilemma.

[0126] At this time, the backup link (i.e., optical fiber) is in hot backup state. The optical fiber conversion module continuously monitors the physical layer status of the link. The transmitted data is converted in real time through the optical fiber conversion module. However, the main switching switch U30 does not select this path, and the transmitted data does not enter the main controller U7.

[0127] The connection between the main controller U7 and the main link transceiver U1 (main link) is used to implement main link copper cable CAN-FD communication, which is the system's default working channel. U7.PA12→U1.TXD / / Send CAN-FD command; U7.PA11←U1.RXD / / Receive slave station response.

[0128] While the main controller U7 is transmitting and receiving main link signals, the entire link is under monitoring, mainly through the following two monitoring paths: First, the bus monitoring path (must pass through the differential multiplexer U34): Main link signal flow: OUT_H / OUT_L port of main switching switch U30 → IN_H / IN_L port of common mode choke U20 → OUT_H / OUT_L port of common mode choke U20 → PAD_IN_H / IN_L port of high frequency ferrite bead U22 → PAD_OUT_H / OUT_L port of high frequency ferrite bead U22 → MAIN_H / MAIN_L port of first monitoring switch U10.

[0129] The PAD_OUT_H / OUT_L ports of the high-frequency magnetic bead U22 are indirectly connected to the MAIN_H / MAIN_L ports of the first monitoring switch U10. In fact, the purified CAN differential signal output by the high-frequency magnetic bead U22 drives the joint module through the J1 connector, and the other path is completely connected to the MAIN_H / MAIN_L ports of the first monitoring switch U10 for monitoring input through the high-impedance network tap without disturbance. The signal path is 100% connected.

[0130] Function: Signals to the external bus are transmitted through a 100kΩ high-impedance network with no disturbance to the taps. After being buffered by the U11 op-amp, the eye diagram is sampled by the U7 ADC for LSTM bit error rate prediction. Monitoring branch current <5μA has an impact of <0.1% on the bus, making it crucial for predictive maintenance.

[0131] Second, the impedance monitoring path (must pass through shunt resistor U12): The CANH and CANL ports of the main link transceiver U1 → FORCE+ / - (parallel) of the shunt resistor U12 → SENSE+ / - of the shunt resistor U12 → IN+ / - of the detection op-amp U13 → OUT port of the detection op-amp U13 → PF4 pin of the main controller U7.

[0132] Function: Monitors bus contact resistance degradation by connecting a 10mΩ precision shunt resistor in parallel. The ADA4522-1 op-amp with a gain of 100 times sends the signal to ADC2 for sampling, which can detect progressive degradation in the 5mΩ range.

[0133] For the fiber optic backup link, it also operates simultaneously in a hot backup state, but data from that backup link is not acquired. The backup link also has health monitoring capabilities: the monitoring capabilities of the ESD-OMC fiber optic conversion module are as follows: 1. ESD-OMC is a "fiber optic conversion module", and the terminating resistor is only an impedance matching component.

[0134] The module integrates an optical transceiver and signal detection circuit, and features: received optical power monitoring (sampling photodiode current via ADC), LOS signal detection (real-time hardware, <1μs response), and bit error rate statistics (internal bit error count). LOS is an abbreviation for Loss of Signal. 2. When the monitoring status is abnormal, the system performs health arbitration: when the optical power is <-20dBm or LOS=1, the backup path is marked as unavailable and switching is prohibited; when the bit error rate is >10... -8 →Mark the backup link as degraded. Before switching, prioritize the healthy link.

[0135] S2: The main controller continuously monitors the link status. If the main link status is abnormal, it instructs the main switch to switch to the fiber optic conversion module and uses the fiber optic conversion module as a backup link to send satellite telemetry and control commands.

[0136] Main link status anomalies include: the bus error counter reaching a first specified threshold, or the signal eye diagram closure exceeding a second specified threshold and the bit error rate exceeding a third specified threshold. Eye diagram closure is a key indicator for evaluating digital signal quality; it describes the degree to which the "eye" in the eye diagram is closed. A smaller closure indicates poorer signal quality, as this typically signifies severe noise, interference, or inter-symbol interference (ISI), making it difficult to accurately determine the optimal sampling point. The second specified threshold is 15%; the third specified threshold is 10%. -7 .

[0137] Bit error rate BER=10 -7 This is a balance between physical layer testability and system fault tolerance margin, not an arbitrary setting. The basis is: CAN FD at 1 Mbps sampling point is located at 60% of the bit time (600 ns); derivation: when the eye diagram closure is 15%, the signal amplitude drops from 2.0V to 1.7V. Due to the doubling of the bit time, inter-symbol interference decreases, and the signal-to-noise ratio (SNR) increases to 16.2 dB. According to the bit error rate formula... The calculated BER is 1.2 × 10⁻⁶. -9In the CAN bus field, CAN FD stands for CAN with Flexible Data-rate, also known as "Variable Data Rate CAN". It is backward compatible with classic CAN, but increases the single-frame data field from 8 bits to 64 bits, and allows the bit rate to be increased to 2 Mbit / s to 8 Mbit / s in the data segment (the arbitration segment remains ≤1 Mbit / s), thereby increasing the effective throughput by 3 to 8 times, while retaining bus arbitration and error checking mechanisms. Bit time = 1 / baud rate. Example: At a baud rate of 1 Mbps, the bit time = 1 / 1,000,000 = 1 μs (microseconds); at a baud rate of 5 Mbps, the bit time = 1 / 5,000,000 = 200 ns (nanoseconds). Conservatively, this scheme still uses BER = 10. -7 As a trigger threshold, a 5dB margin is reserved to avoid false triggering due to environmental noise fluctuations; Effectiveness: This threshold theoretically guarantees a 200ms warning window (capable of transmitting 1562 frames), and the 150ns switching time accounts for only 0.000075% of the window. Margin: 10 -6 The CAN controller error warning threshold (96 error frames) is approaching; switching too late at this point will result in frame loss. -8 A longer window is needed, the warning delay is >500ms, and the approach to robot joints is too conservative; 10 -7 Approximately 200ms in advance, which is exactly greater than the longest frame time plus 150ns for the solid-state switch, achieving 0 frame loss; 10 -7 It is the optimal compromise of "measurable, timely, and not conservative".

[0138] The main switching switch U30 continuously monitors the main link signal quality, while the on-chip ADC of the main controller U7 acquires the data and DMA moves it to the buffer queue. It checks if the eye diagram closure is greater than or equal to 15%. If not, it continues monitoring the main link; if so, it checks if the BER (bit error rate) is greater than or equal to 10. -7 Otherwise, continue monitoring the main link. If a frame is lost, perform a predictive trigger switch. The GPIOx port of the main controller U7 is set to 0, the main switch U30 switches to the backup link (fiber optic) for less than 150ns, 0 frames are lost, the system marks "main link failure", and a maintenance prompt pops up.

[0139] The main controller U7 collects the following monitoring parameters: ① Copper cable eye diagram closure: real-time monitoring of signal edge distortion; ② Fiber optic received optical power: monitoring optical link attenuation; ③ Slip ring contact impedance: quantifying carbon brush wear through a "careful buffering" mechanism. When the monitored parameters deteriorate to the fault threshold 200ms in advance, the system reports a maintenance request in advance, realizing "predictive maintenance" rather than "fault-based switching".

[0140] It should be noted that the main switch U30 is triggered under only the following two conditions: Condition 1: Bus error counter triggered; Threshold: Typically 96 (Error Warning threshold) or 128 (Error Passive threshold); Features: Triggered by a single condition, requiring no other parameters.

[0141] Condition 2: Triggered by both eye diagram closure degree and bit error rate; Threshold example: Eye diagram closure > 15% and bit error rate > 10 -7 ; Feature: Both sub-conditions must be met simultaneously; neither can be omitted.

[0142] As for the three monitoring parameters, "copper cable eye diagram closure, optical fiber received optical power, and slip ring contact impedance", they are dedicated to predictive maintenance and are in parallel with fault switching conditions. Copper cable eye diagram closure is used for both predictive maintenance and fault switching; The optical power received by the fiber optic cable is only used to predict fiber optic link degradation and replace the optical module in advance. Slip ring contact impedance is only used to predict slip ring life and allow for early maintenance.

[0143] The connection between the main controller U7 and the CAN-to-fiber optic module U15 (backup link) is used to realize the backup link fiber optic CAN communication, and is the standby channel after the main switch U30 switches over. U7.PB6→U15.TXD / / Send CAN-FD command (after level conversion); U7.PB5←U15.RXD / / Receive slave station response (after level conversion).

[0144] The switching process is as follows: Status monitoring and switching triggering (corresponding module and interface operation): The main controller U7 (with built-in ADC module) serves as the detection core, acquiring signals from the main link (main switching switch U30, first monitoring switch U10, second monitoring switch U32, differential multiplexer U34) via the on-chip ADC to monitor the main link status in real time; when the main link eye diagram closure is detected to be ≥15% and the bit error rate is ≥10%, the system will detect the main link status. -7 When the main link is found to be abnormal, a switching command is triggered. At this time, the GPIO output port (i.e., GPIOx port) of the main controller U7 outputs a low-level control signal, which is transmitted to the control terminal of the main switching switch U30, instructing it to switch to the backup link.

[0145] Switching command transmission and execution (corresponding interface action): The FDCAN-TX port (CAN transmitter) of the main controller U7 sends a switching control signal, which is transmitted to the control terminal of the main switching switch U30 after signal conditioning by the level conversion module U31 (U31_A and U31_B). After receiving the command, the main switching switch U30 responds at its control terminal (i.e., IN port), and the internal switch is activated to disconnect the signal transmission of the main link (copper cable) and connect the signal channel of the backup link (fiber optic cable). The entire switching process is completed by hardware without software intervention, and the switching delay is ≤10μs.

[0146] Backup link data transmission (corresponding data flow direction): After the switch is completed, the FDCAN-TX port of the main controller U7 continues to send CAN bus signals. The signals are converted into optical signals by the CAN-to-fiber optic module U15 of the backup link and transmitted to the slave station through the optical fiber. The optical receiving module U3 of the slave station (the optical receiving module U3 is an integrated internal functional unit of the fiber optic to CAN module U41, which is matched with the CAN-to-fiber optic module U15 on the main station side and is used to receive the backup link optical signals transmitted through the J2 connector) receives the optical signals, converts the optical signals into electrical signals through its RX port, and then, after being conditioned by the level conversion module U31, outputs them to the slave controller through its OUT port to realize normal data transmission.

[0147] 4. Status Feedback and Confirmation (Corresponding Interface Functions): The feedback port of the main switch U30 (i.e., the FLT port, used to output the main / backup link switching completion / fault status signal) feeds back the switching completion signal to the ADC acquisition port (GPIOy port) of the main controller U7. The main controller acquires the feedback signal through the ADC, confirms the successful switching, and marks the main link as faulty, thus completing the entire switching process.

[0148] The PLC controller U40 achieves passive fault switching by monitoring the CAN error frame count (the count of the bus error counter). In a dual-bus heterogeneous redundancy system, the CAN error frame count refers to the statistical accumulation of error events at the CAN bus physical layer or data link layer. As one of the core quantitative indicators for judging the health of the bus, it, together with the eye diagram closure, constitutes a dual criterion for switching decisions. The CAN error frame count is the system's "health heartbeat monitor," forming a "double insurance" with the eye diagram closure, ensuring accurate switching only when "communication is still possible but about to fail," avoiding erroneous or missed switching.

[0149] During the switching process, the data buffered in the FIFO is still transmitted through the existing CAN communication line between the main controller U7 and the main switching switch U30. The specific path is as follows: When the switch is triggered, the main controller U7 freezes its own TX / RX FIFO, and the data being sent / received is temporarily stored in the 128-byte FIFO inside the main switch U30.

[0150] The main switching switch U30 maintains a temporary storage of the buffered frame until the hardware switching is completed within 150ns.

[0151] After the hardware switch is completed, the main switch U30 automatically sends the frames in the internal FIFO through the backup link (fiber optic conversion module) after the switch.

[0152] Meanwhile, the main controller U7's DMA restores the TX / RX FIFO, enabling seamless data transfer continuation.

[0153] That is, the cached data is first stored inside the main switch U30. After the switch is completed, the main switch U30 sends it out through the newly selected backup link, without the need to add a new line.

[0154] S3: The main controller continuously monitors the link status. If the main link status returns to normal, it instructs the main switch to switch to the main link transceiver as the main link to send satellite telemetry and control commands.

[0155] Continuously monitor the main link recovery and determine if the BER is less than 10. -7 If the cycle continues for 200ms, the backup link is maintained and monitoring for recovery continues. If the cycle is successful, self-healing back-off is executed, the GPIOx port of the main controller U7 is set to 1, and hardware loop monitoring continues.

[0156] When switching the main switch U30, store the frame to be sent, and send the frame after the switching is completed.

[0157] Closed-loop monitoring is achieved through station response and status feedback.

[0158] Synchronous switching of return channels: The TX / RX channels of the main switch U30 are switched to ensure that the response data path of the slave station (joint module) is consistent with the transmission path. Among them, the TX interface (transmit interface) is the abbreviation for the OUT_H / OUT_L pins of the main switch U30; the RX interface (receive interface) is the abbreviation for the IN_H / IN_L pins of the main switch U30; the input pins of the main switch U30 are the receive ports, and the output pins are the transmit ports. Online monitoring data injection: A 2-byte link quality code (eye diagram closure, optical power attenuation value) is automatically appended to the returned data packet. The main controller U7 receives this code via its internal DMA controller and stores it in the "careful buffer" queue. The DMA controller, integrated within the main controller U7, includes channel 1 and channel 2. Channel 1 moves the FDCAN1 receive FIFO data to SRAM_RX, and channel 2 moves the SRAM_TX data to the FDCAN1 transmit FIFO. During the switching of the main switch U30, the DMA controller continues to operate, ensuring that data buffering and retransmission are not interfered with by the CPU. Predictive maintenance: When the slip ring carbon brush wear causes impedance drift >5Ω, the system will issue a warning 200ms in advance, instead of switching after the fault occurs; The direct solution is to upgrade from "fail-safe switching" to "predictive maintenance," which meets the requirements of unattended stations.

[0159] S4: Repeat steps S2 and S3 to ensure uninterrupted operation of the ground station antenna dual-bus heterogeneous redundant communication system.

[0160] Throughout the process, the status of the main controller is continuously monitored. If the main controller fails, the PLC controller controls the main switching switch to switch between the main link and the backup link.

[0161] As shown in Table 20, the steps of this solution mainly solve the three technical problems in the table below. By using centralized hardware adjudication and heterogeneous media redundancy, the traditional "distributed collaborative redundancy" is transformed into "master-side transparent redundancy", which fundamentally reconstructs the implementation paradigm of dual CAN redundancy.

[0162] Table 20

[0163]

[0164] In summary, this solution addresses the issue of simultaneous failure by using two different cable types; it determines the switching timing between the primary and backup links based on signal eye diagram closure, enabling online monitoring and resolving the technical problem of frame loss during post-switching; and it improves switching efficiency by using a main switching switch to switch between the primary and backup links, thereby enhancing communication reliability, reducing maintenance costs, and decreasing the failure rate. Specifically, it achieves the following technical effects: 1. Communication reliability improved by a significant margin; System availability R(t) > 0.999999 (theoretical + measured); Switching latency is less than 150 ns, which is 200 times shorter than existing FPGA / software solutions, achieving zero frame loss; Antenna pointing error increment <0.003° (C-band beamwidth 0.5°).

[0165] 2. Maintenance costs and downtime are reduced to zero; Zero modifications to the slave station, no firmware or hardware upgrades required in the field; MTTR=0, self-healing back-cut <1s, maintenance without shutdown; Annual maintenance costs for remote, unattended sites are reduced by 80%.

[0166] 3. The dual differences between patents and BOM; It has no VIO transceiver, no FPGA, and no external monitoring MCU, which is different from the three existing patents. The BOM cost is reduced by 0.32 USD / node, the weight is <8g, and it can directly embed a Φ20mm slip ring.

[0167] 4. Predictive maintenance and risk quantification; In-chip ADC eye diagram sampling provides 200ms early warning of slip ring carbon brush wear and cable aging; It supports risk probability P quantification, providing data basis for maintenance planning, and MTBF prediction error <5%. MTBF is an abbreviation for Mean Time Between Failures.

[0168] 5. Versatility and plug-and-play functionality; Suitable for real-time control scenarios such as ground station antennas, radar turntables, and anti-aircraft gun servos; POF is plug-and-play in the field, requiring no welding, and has electromagnetic interference resistance >40dB, reducing the failure rate by 90% during thunderstorm seasons.

[0169] According to a third embodiment of the present invention, the present invention provides a ground station antenna dual-bus heterogeneous redundancy communication system, which is basically the same as the ground station antenna dual-bus heterogeneous redundancy communication system of the first embodiment, such as... Figure 4 As shown, the difference lies in the integration of the board. The core concept is to make the heterogeneous redundant gateway into a PCIe board and directly plug it into the main controller. Key technical features include a PCIe Gen3 x4 interface, FHFL size, eliminating the need for an external box and power supply. Applicable scenarios include new ground station cabinets, saving space.

[0170] According to a fourth embodiment of the present invention, the present invention provides a ground station antenna dual-bus heterogeneous redundancy communication system, which is basically the same as the ground station antenna dual-bus heterogeneous redundancy communication system of the first embodiment, such as... Figure 5 As shown, the difference lies in the fact that, through Ethernet heterogeneity, the core concept is to replace the POF fiber with 10BASE-T1S single-pair Ethernet for backup links; the key technical points are: using the LAN8670 PHY chip, connecting the MCU to the MII interface, and encapsulating CAN frames into Ethernet frames; the advantages are: reusing existing rack twisted-pair cables and rapid transformation.

[0171] According to a fifth embodiment of the present invention, the present invention provides a ground station antenna dual-bus heterogeneous redundancy communication system, which is basically the same as the ground station antenna dual-bus heterogeneous redundancy communication system of the first embodiment, such as... Figure 6As shown, the difference lies in the use of an edge FPGA. The core concept is that the prediction module is made using an FPGA, without the need for an on-chip ADC in the MCU. Key technical points: The FPGA has a built-in ADC and comparator, with a latency of <1ms. Applicable scenarios: The main control MCU does not have an ADC or has insufficient resources.

[0172] According to a sixth embodiment of the present invention, the present invention provides a ground station antenna dual-bus heterogeneous redundancy communication system, which is basically the same as the ground station antenna dual-bus heterogeneous redundancy communication system of the first embodiment, such as... Figure 7 As shown, the difference lies in the use of a wireless backup link. The core concept is that the backup link uses 5G-UWB wireless instead of POF fiber. Key technologies include the DW3000 module, 6-8.5GHz, and AES-256 encryption. Applicable scenarios include mobile components such as antenna extension arms where cabling is difficult.

[0173] Exemplary embodiments of the present invention have been specifically shown and described above. It should be understood that the present invention is not limited to the detailed structures, arrangements, or implementations described herein; rather, the present invention is intended to cover various modifications and equivalent arrangements contained within the spirit and scope of the appended claims.

Claims

1. A ground station antenna dual-bus heterogeneous redundancy communication system, characterized in that, include: Main controller, main switching switch, main link transceiver, analog signal conditioning and monitoring circuit, differential multiplexer, first monitoring switch, second monitoring switch, dual MCU arbitration OR gate, fiber optic conversion module, main link copper cable, plastic optical fiber, and multiple joint modules; Multiple joint modules, including a first joint module; The main controller is connected to the main switching switch and is used to control the main switching switch to switch between the main link and the backup link; the main controller is connected to the dual MCU arbitration OR gate and is used to issue link switching commands; the main switching switch is connected to the dual MCU arbitration OR gate and is used to receive the main and backup channel switching commands issued by the main controller to realize hardware switching. The main switching switch is connected to the main link transceiver and the fiber optic conversion module, and is used to switch between the main link transceiver and the fiber optic conversion module. The main link transceiver is connected to the main link copper cable and is used to send satellite telemetry and control commands; The fiber optic conversion module is connected to a plastic optical fiber and is used as a backup link to send satellite telemetry and control commands; the fiber optic conversion module includes a CAN to fiber optic module and a fiber optic to CAN module. The fiber optic to CAN module is connected to the first joint module; The first monitoring switch is connected to the main link transceiver, and the second monitoring switch is connected to the CAN-to-fiber module. The differential multiplexer is connected to the first monitoring switch to monitor the differential positive and differential negative of the main link; the differential multiplexer is connected to the second monitoring switch to monitor the differential positive and differential negative of the backup link. The analog signal conditioning and detection circuit is connected to the differential multiplexer. After selecting one of the two links, the differential multiplexer and the backup link, it outputs the CAN differential positive signal of that link to the analog signal conditioning and monitoring circuit for eye diagram monitoring. The analog signal conditioning and monitoring circuit is connected to the main controller and is used to monitor the signal eye diagram closure. The main controller controls the main switching switch to switch between the main link and the backup link based on the signal eye diagram closure. It also includes a PLC controller, which is connected to the main controller and is also used to monitor the bus error counter and report it to the main controller. The main controller controls the main switching switch to switch between the main link and the backup link according to the bus error counter count. The PLC controller is connected to the main switching switch and acts as a backup controller for the main controller. When the main controller fails, it controls the main switching switch to switch between the main link and the backup link. The dual MCU arbitration OR gate is connected to the PLC controller to receive passive takeover signals from the PLC controller. The main controller fails when the main controller heartbeat times out by 100ms or the Error Counter is greater than 96. It also includes a suppression circuit, which comprises a common-mode choke, a TVS protection device, and a high-frequency ferrite bead; the common-mode choke is connected to the TVS protection device, the high-frequency ferrite bead, and the main switching switch; The high-frequency magnetic bead is connected to the PLC controller and then to the first joint module via a J1 connector.

2. The ground station antenna dual-bus heterogeneous redundant communication system according to claim 1, characterized in that, It also includes a detection operational amplifier and a shunt resistor. The shunt resistor is connected to the main link transceiver and the detection operational amplifier. The detection operational amplifier is connected to the main controller and is used to send an analog value of the contact impedance to the main controller to monitor whether the copper cable equipment of the main link needs to be replaced.

3. A ground station antenna dual-bus heterogeneous redundancy communication method, characterized in that, The ground station antenna dual-bus heterogeneous redundancy communication system according to any one of claims 1 or 2 includes the following steps: S1: The system powers on and selects the main link transceiver as the main link to send satellite telemetry and control commands; S2: The main controller continuously monitors the link status. If the main link status is abnormal, it instructs the main switch to switch to the fiber optic conversion module and uses the fiber optic conversion module as a backup link to send satellite telemetry and control commands. S3: The main controller continuously monitors the link status. If the main link status returns to normal, it instructs the main switch to switch to the main link transceiver as the main link to send satellite telemetry and control commands. S4: Repeat steps S2 and S3 to ensure uninterrupted operation of the ground station antenna dual-bus heterogeneous redundant communication system.

4. The ground station antenna dual-bus heterogeneous redundancy communication method according to claim 3, characterized in that, In step S2, the abnormal status of the main link includes: the bus error counter count reaches a first specified threshold, or the signal eye diagram closure is greater than a second specified threshold and the bit error rate is greater than a third specified threshold.

5. The ground station antenna dual-bus heterogeneous redundancy communication method according to claim 4, characterized in that, The second specified threshold is 15%, and the third specified threshold is 10%. -7 .

6. The ground station antenna dual-bus heterogeneous redundancy communication method according to claim 3, characterized in that, Throughout the process, the status of the main controller is continuously monitored. If the main controller fails, the PLC controller controls the main switching switch to switch between the main link and the backup link.

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